It is known to design power supply, converter, and charger systems to receive an AC power source as input power, and to convert the AC power to DC power for the output. A disadvantage of many such systems is that they remain active, and consume power, even when there is no load on the output. Such systems, configured for using an AC power source for powering electronic apparatus and/or for charging DC energy storage apparatus, such as batteries, are common. Frequently, such AC/DC adapters and chargers are left plugged in to an AC source even when no DC power is required. In other words, they continue to convert their AC input into DC for output, thereby consuming power, even when no output is needed. The AC/DC converter topologies commonly used in the arts tend to share this same basic characteristic due to their physical and electrical structure. This inherently leads to decreased efficiency and possibly a reduction in system longevity.
Due to these and other problems and potential problems with the current state of the art, improved methods, apparatus, and AC/DC conversion and charger systems would be useful and advantageous additions to the art.